Subject: MICROWAVE ANTENNA too close?? (Curry).
Date: Wed, 18 Oct 2000 123603 -0500
From: Roy Beavers
To: guru
--------------------------------------------------
.........From EMF-L......
Bill Curry's answer to a question about a "close by" MW antenna should
be seen by all....... Thanks, Bill......guru.....
-------- Original Message --------
Subject: Re: [Fwd: MICROWAVE ANTENNA]
Date: Wed, 18 Oct 2000 12:30:38 -0500
From: "Bill P. Curry"
Reply-To: BPCurry@MCS.com
Organization: EMSciTek Consulting co.
To: roy@emfguru.com
References: <39EC84E2.1A32AADE@emfguru.com>
Roy and Armand,
The amperage rating of the antenna doesn't really give you enough information.
They are saying that the current must never exceed that value. You need to
know the actual power put into the anenna and the gain characteristics of the
antenna. Probably, the antenna focuses the radiation into specific
directions, and the amount of focusing is indicated by the gain. This means
that if the antenna's maximum gain direction points toward you, you will
receive more radiation than if all the radiaiton were emitted equally in all
directions. As a general rule, if you can see that the pod is pointing toward
you, you are probably in the region of maximum gain. Also, 100 feet seems to
me to be too close to the anenna to be safe, if it is pointing at you.
To be able to estimate the radiation density and thus have a means of
comparing your estimate with published tables of biological effects that have
been found at various radiation densities, you need at least the following
minimal information: 1) frequency of the radiation, 2) maximum power of the
transmitter into one channel, 3) maximum number of channels that will likely
be active simultaneously, 4) antenna gain as a function of direction in both
horizontal and vertical planes.
The best way to get equivalent information is to try to find what municipal
agency approved the installation of the antenna and get a copy of the
application that was required for approval. This should give you the type of
transmissions (e.g., analog cell phone, digital PCS in the U.S. or GSM in
Europe), frequency, perhaps transmitter manufacturer and model number, antenna
manufacturer and model number.
Knowing this information, one can usually get the antenna gain pattern from
the manufacturer, and the application will probably tell you either the
maximum gain or the Effective Isotropic Radiated Power (EIRP) or the Effective
Radiated Power. From all this information pus the horizontal and vertical
distance between you and the antennas, the radiation power density at your
location can be calculated for comparison with power densities known to
produce specific biological effects. If you can get this information, I will
be happy to perform the radiation density calculations for you, gratis. Also,
you can find some of the reported biological effects resulting from
irradiation at various power densities at www.ccwti.org. Click on the tab
marked "science." These tables are currently being updated. Good luck.
Roy Beavers wrote:
>
> Bill:
>
> What do you think??? .....guru......
>
> -------- Original Message --------
> Subject: MICROWAVE ANTENNA
> Date: Tue, 17 Oct 2000 12:45:44 EDT
> From: Sharmie@aol.com
> To: ROY@emfguru.com
>
> THE ANTENNA DIAGONALLY ACROSS THE STREET FROM IS HAS A 200 AMP RATING WITH
> THREE PODS POINTING IN DIFFERENT DIRECTIONS FROM EACH CORNER OF A FIVE STORY
> BUILDING ROOF TOP THAT OCCUPIES A FULL SQUARE BLOCK.
> WE ARE IN A HIGHRISE CONDO BUILDING ON THE TOP FLOOR, ABOUT 100 FEET DISTANT
> FROM THE POD POINTING IN OUR DIRECTION.
> DO THESE FACTS SUPPLY ENOUGH INFO SO THAT YOU CAN TELL ME IF THERE IS ANY
> DANGER TO US FROM MICROWAVE RADIATION? THANK YOU. YOURS TRULY, ARMAND
--
----
Bill P. Curry, Ph.D. |Physics is fun.
EMSciTek Consulting Co. |Trying to make a living!
22W101 McCarron Road, |Phone: (630) 858-9377
Glen Ellyn, IL 60137 |Fax: (630) 858-9159 with prior notice
Web page: http://www.EMSciTek.com
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Archive provided courtesy of WaveGuide, http://www.wave-guide.org
Reprinted with permission of Roy Beavers, http://www.emfguru.com